An Awk Primer/Numbers and Strings

An Awk Primer

Numbers

Numbers can be expressed in Awk as either decimal integers or floating-point quantities. For example:

789
3.141592654
+67
+4.6E3
-34
-2.1e-2

There is no provision for specifying values in other bases, such as hex or octal; however, as will be shown later, it is possible to output them from Awk in hex or octal format.

Strings

Strings are expressed in double quotes. For example:

"All work and no play makes Jack a homicidal maniac!"
"1987A1"
"do re mi fa so la ti do"

Awk also supports null strings, which are represented by empty quotes: "".

Like the C programming language, it is possible in Awk to specify a character by its three-digit octal code (preceded by a backslash).

There are various "special" characters that can be embedded into strings:

\n Newline (line feed)
\t Horizontal tab (aligns to next column of 8 spaces)
\b Backspace
\r Carriage return
\f Form feed (possibly causes a new page, if printing)

A double-quote (") can be embedded in a string by preceding it with a backslash, and a backslash can be embedded in a string by typing it in twice: \\. If a backslash is used with other characters (say, \m), it is simply treated as a normal character.